also, visit Clarke Quay at night and ride the GMAX (reverse bungee. it's one of the coolest rides ever!!! http://jotan23.blogspot.com/2008/03/sing...
if you're into shopping, there's also Bugis and Mustafa.
Street dining is also popular in Lau Pa Sat. Try the BBQ'd Stingray! YUM!

if you're into Zoos, you may visit their Night Safari or Jurong Bird park :)
http://jotan23.blogspot.com/2008/03/singapore-galore-part-4-jurong-bird.html

other unique and fun things to do and eat in Singapore:
DHL balloon,dive with the sharks,flying trapeze,roti prata, lassi,singapore flyer, night safari
http://jotan23.blogspot.com/2008/06/other-fun-and-unique-things-to-do-in.html

HAVE FUN!!!
http://jotan23.blogspot.com/2008/03/uniquely-singapore.html